Will,I'm not the one to answer your binding question. Watch the slo mo video and stop the action at various points. On many of the turns you have done a good job of foot pullback after release, with good fore-aft position in the hi-C. However, on some of the shorter turns you seem to stay flexed throughout the turn, even at the apex. The one thing I consistently see is lack of CA. You mentioned Angry Mother drills, but I couldn't see any on the videos you posted.

The bindings I am using right now PRX12. I have read somewhere on the forum that PRD14 is more suitable for PMTS due to its dimensions.

The major difference between the PRX and PRD bindings is the heel/toe height delta, the PRX having a higher delta than the PRD. Which is better is an individual matter that's difficult to predict - as several anatomical factors are involved. Experimentation under the guidance of a PMTS-qualified coach and fitter would be the preferred way to find out.

I'm also mystified at your reference to "Angry Mama", as no Angry Mother drills appear in these two videos. As rwd noted, there is little CA or CB in this skiing. Nor is there much flexion or (especially) extension of the legs. PMTS skiing employs a greater range of motion in these areas.

You also listed Super Phantoms, but I didn't see many. There was only occasional commitment to the LTE of the new stance ski during transition. The best way to learn this (or nearly any) new movement is by exaggeration. After flexing into the release and lightening/lifting the new free ski, stay on the LTE of the new stance ski for a S-L-O-W count to three. Glide on the LTE and think one hippopotamus - two hippopotamus - three hippopotamus... THEN tip the free ski and CA like crazy to move your body inside the turn and allow the stance ski to change edges. This takes conscious practice... LTE balance is not a movement that many people acquire naturally.

All that said, my (unqualified) summary of your SMIM would be... more tipping.

At first glance that's nice skiing, better than the PSIA model by far. Some small refinements, that can really enhance the final picture, inside foot pull back, made it stronger, pole tap timing with coordinated flexing, this will help a stronger CA, timed with engagement.